Luke is teacher, Jaden, the brand new jedi knight.... light side ending is canon for crying out loud, Luke never fought Jaden, and there is no indication that Jaden had anywhere near the level of power of either Kyle or Luke. Heck, check their statistics through cheat codes if you have no other source. Luke has 200 force points, while Jaden only has one hundred. Jaden doesn't even defeat Kyle in an all out fight in his final duel in the dark side ending, Kyle is constantly trying to disarm Jaden, and like grab him or whatever that move is.
Basically the only way to defeat kyle, on difficult is to constantly use force drain or force heal. In fact, that's pretty much the only way to defeat almost any larger group of enemies on difficult level (or master or whatever). Since its pretty much common knowledge, that in a light saber fight, someone cannot take a light saber cut across the face, or the shoulder, or the leg, and then jump away, and run down a hallway, and heal yourself in 10 seconds, or eat magical healing potions (the health packs, they don't work instantaneously.) Also: NO ONE uses shields in a light saber battle.
If you try to take a video game like JA, and turn the characters into true duelers, great, but it doesn't make it real. I mean, if you want to: a stormtrooper with a lightsaber can kille 3 lukes and 7 kyles, as long as he keeps using drain or heal, and you are a really good player. My point is, you have to use all the other sources you have as well, and if they are considered, luke wins, easily.